Stuttering when I add video fx
 

I am a new h1 and Vegas 7 user. I was having gobs of trouble with stutter and interlacing problems. Long story short, don't be a fool like me. Capture and render to your slave drive. WELL, I thought that I had solved my problems but, now, when I add video fx like changing the color to studio RGB the stutter is back.
My question is...Am I having processor problems, RAM problems or both? I am thinking about upgrading to a 10000 RPM hard drive to replace my 7200 RPM drive in hopes of solving the problem. I have 2 gigs of RAM. and a 3 GIG processor. I am also getting stutter when I burn in DVD architect.
Thoughts?